Cure monitoring has received considerable interest for industrial applications
that use thermosetting resins and advanced composites. In these applications, the degree of curing is critical for the structures’ high quality and
performance. This paper demonstrates the excitation of Lamb waves with low
profile surface mounted piezoelectric transducers for the characterisation
of symmetric composite laminates at different cure levels. The response signals
were processed by extracting their instantaneous characteristics through ensemble
empirical mode decomposition. The paper investigates the potential benefit
from the use of piezoelectric transducers, which could monitor the life cycle
of complex composite structures from the early manufacturing stages to the
later aging stages. In these stages, structural monitoring is essential for
the prevention of possible catastrophic damage. The response signals successfully
captured the different cure levels, and the employed analysis showed good
agreement with the increasing cure degree.
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